The Rato R225 is a 223 cc (13.6 cu-in) single-cylinder air-cooled 4-stroke internal combustion general-purpose gasoline engine with vertical shaft manufactured by Chongqing RATO Holding (Group) CO., LTD for different applications: lawn mowers, mini-tillers, High-pressure washers, shredders.
The Rato RV225 engine has a single-cylinder with a vertical shaft; an overhead valve (OHV) design; flat suction valve carburetor; dual element air filtration system; capacitance discharge type or inductance discharge type ignition system; centrifugal mechanical governor system and recoil starter.
A 70.0 mm (2.76 in) cylinder bore and 58.0 mm (2.28 in) piston stroke give the Rato R225 motor a total of 223 cc of displacement. Compression ratio rating is 8.3:1. It produced 4.0 kW of horsepower at 3,600 rpm and 12.5 N·m (1.27 kg·m, 9.2 ft·lb) of torque at 2,500 rpm.
General information
| Engine Specifications | |
| Model | RV225 |
| Type | 4-stroke, OHV, single cylinder |
| Displacement | 223 cm 3 (13.6 cu-in) |
| Max. horsepower | 4.0 kW at 3,600 rpm |
| Max. torque (crank PTO) | 12.5 N·m (1.27 kg·m, 9.2 ft·lb) at 2,500 rpm |
| Carburetor | Flat suction valve carburetor |
| Cooling system | Forced-air |
| Ignition system | Capacitance discharge type or inductance discharge type |
| Lubricating system | Splash |
| Starting system | Recoil / electric starter |
| Stoping system | Ignition primary circuit ground |
| Fuel used | Unleaded gasoline (octane number 86 or higher) |
| PTO shaft rotation | Counterclockwise (from PTO shaft side) |
Cylinder Block and Head
| Cylinder block | ||
| Compression ratio: | 8.3:1 | |
| Bore x Stroke | 70 X 58 mm (2.76 x 2.28 in) | |
| Sleeve internal diameter | 70.00 mm (2.7559 in) | |
| Piston skirt outer diameter | 69.985 mm (2.7553 in) | |
| Number of piston rings (compression / oil): | 2 / 1 | |
| Ring side clearance | Top/Second | 0.015-0.045 mm (0.0006-0.0018 in) |
| Ring end gap | Top/Second | 0.20-0.40 mm (0.008-0.016 in) |
| Oil | 0.15-0.35 mm (0.006-0.014 in) | |
| Ring width | Top/Second | 1.5 mm (0.060 in) |
| Oil | 2.0 mm (0.079 in) | |
| Connecting rod small end ID | 18.005 mm (0.7087 in) | |
| Connecting rod big end ID | 30.02 mm (1.182 in) | |
| Crankshaft crank pin outer diameter | 29.98 mm (1.180 in) | |
| Cylinder Head | ||
| Warpage (limit) | 0.10 mm (0.004 in) | |
| Valve Arrangement: | OHV | |
| Valves: | 2 | |
| Stem outer diameter (standard): | INTAKE | 5.48 mm (0.216 in) |
| EXHAUST | 5.44 mm (0.214 in) | |
| Cam height: | INTAKE | 27.7 mm (1.09 in) |
| EXHAUST | 27.75 mm (1.093 in) | |
| Valve spring free length: | 34.0 mm (1.3386 in) | |
| Camshaft journal diameter: | 13.984 mm (0.5505 in) | |
Service Information
| Engine | |
| Maximum speed | 3800 ± 200 rpm |
| Cylinder compression | 12.0 kg/cm2 at 1400 rpm |
| Valve clearance | |
| Intake valve clearance | 0.15±0.02 mm (0.006±0.001 in) |
| Exhaust valve clearance | 0.20±0.02 mm (0.008±0.001 in) |
| Oil system | |
| Oil type | 4-stroke or an equivalent (SJ) |
| Recommended oil | SAE 10W-30, 15W-40 |
| Oil capacity | 0.6 L |
| Ignition system | |
| Spark plug | NGK: BPR6ES |
| Spark plug gap | 0.7-0.8 mm (0.028-0.031 in) |
Author:
need 2 find an English service manual for the Rato RV225.
i just got me the rv225 motor. did you ever find out whereto get a manual.
Can I please get a repair manual for rato rv200 or rv225
Je recherche un manuel d’entretien et utilisation en français du moteur RV225
Merci pour votre aide Cordialement
I just got a RATO 7.0 RV225-X and it has NO primer bulb (unless it’s seriously hidden). How to start without it? Oh ya, an success tracking down a service/repair manual?